| 摘要 |
The butterfly valve includes a body having a cylindrical bore, a continuous internal groove in the bore and a resilient O-type, sealing ring mounted in the groove. Rotatably mounted in the bore for shutting off flow is a valve member which preferably is disc-shaped and includes a peripheral seating surface of spherical shape for sealingly engaging the sealing ring when the valve is in a closed position. The valve member also includes a plurality of circumferentially spaced retainers, such as a plurality of axially extending fins located on the opposite sides of the disc and having a curvilinear outer face, which slidably engage normally unrestrained sections of the sealing ring and mechanically retain these sections against dislodgment from the groove during valve operation, particularly by the differential fluid forces existing across the valve member during initial opening and final closing. |
